Electronic assemblies designed for harsh environments can be overmolded with a plastic encapsulant, as shown for example in the U.S. Pat. Nos. 6,180,045 and 6,307,749, assigned to the assignee of the present invention. In certain applications, it is desired to insert-mold a connector header into the module; see for example the U.S. Pat. No. 6,779,260, also assigned to the assignee of the present invention, in which a horizontal mount connector header is insert-molded into an electronic module. Connector pins captured in the connector header are soldered to the circuit board, and the plastic encapsulant encases the circuit board and a portion of the connector header to form a sealed module.